1. Field of the Invention
The present invention relates to a semiconductor device and a method of manufacturing the same, an apparatus for manufacturing a semiconductor device, a circuit board and an electronic instrument.
2. Descriptions of the Related Arts
As the electronic devices are recently manufactured to be more miniaturized, there is a demand for semiconductor device packages suitable for a high-density mounting. To answer these demands, surface-mounted packages such as Ball Grid Array (BGA) and Chip Scale/Size Package (CSP) have been developed. With these surface-mounted packages, a semiconductor chip is mounted by face-down bonding on a substrate on which an interconnecting pattern is formed.
In order to make a positional alignment of the interconnecting pattern with electrodes of the semiconductor chip, a conventional method of manufacturing the surface-mounted package uses an optical system. Specifically, the optical system is placed between a surface having electrodes of a semiconductor chip and a surface having an interconnecting pattern of a substrate, and images of both surfaces are taken by a camera, thus detecting the positions of the interconnecting pattern and electrodes. According to this method, because the optical system is complicated, errors in positioning are apt to occur, so that a degradation of mounting precision is brought about.
The present invention was made to solve the above problem, and an object of the present invention is to provide a method of manufacturing a semiconductor device which improves the mounting precision, the semiconductor device manufactured by the method, an apparatus for manufacturing the semiconductor device, a circuit board, and an electronic instrument.
(1) According to a first aspect of the present invention, there is provided a method of manufacturing a semiconductor device that comprises a flexible substrate including a base substrate that has a light transmission property and an interconnecting pattern formed on one surface of the base substrate, and a semiconductor chip that is connected to the flexible substrate and provided with electrodes, the method comprising the steps of:
detecting a position of at least one of the electrodes and interconnecting pattern by a detection means that is provided on a side opposite to a side on which the semiconductor chip is provided; and
electrically connecting the interconnecting pattern to the electrodes.
(2) In this method of manufacturing a semiconductor device, positions of the interconnecting pattern and the electrodes may be detected by the detection means by viewing from a surface of the flexible substrate opposite to a surface on which the interconnecting pattern is formed.
Since the substrate having a light transmission property is used, the interconnecting pattern can be recognized from the reverse surface of the flexible substrate. When the surface on which the interconnecting pattern is formed and the surface on which the electrodes are formed are arranged parallel to each other, the recognition can be made without changing the direction of the detection means. Moreover, by moving the flexible substrate and the semiconductor chip in a direction parallel to these surfaces, the face down bonding can be performed after the recognition. As a result, it is possible to enhance a mounting precision without using a complicated optical system.
(3) In this method of manufacturing a semiconductor device, the flexible substrate may be a two-layered flexible substrate in which the interconnecting pattern is formed on the base substrate without using adhesive.
Generally-used adhesive inhibits light to transmit through the flexible substrate. By using the two-layered substrate that does not use such generally-used adhesive, the interconnecting pattern can be recognized through the surface opposite to that where the interconnecting pattern is formed.
(4) In this method of manufacturing a semiconductor device, the interconnecting pattern may be formed on the base substrate by sputtering.
As described above, by forming the interconnecting pattern on the substrate by sputtering, the interconnecting pattern can be easily recognized from the side opposite to that where the interconnecting pattern is formed.
(5) In this method of manufacturing a semiconductor device, the base substrate may be formed of polyethylene terephthalate.
Polyethylene terephthalate is an example of a material that has the light transmission property.
(6) In this method of manufacturing a semiconductor device, the detection means may comprise a camera; positions of the interconnecting pattern and the electrodes may be detected by the camera; and the camera may take an image of one of the flexible substrates having the interconnecting pattern and the semiconductor chip having the electrodes first, and then takes an image of the other.
(7) In this method of manufacturing a semiconductor device, the camera may move in a direction parallel to surfaces on which the interconnecting pattern and the electrodes are formed to take an image of one of the interconnecting pattern and the electrodes.
(8) According to a second aspect of the present invention, there is provided a semiconductor device manufactured by the above-described method.
(9) According to a third aspect of the present invention, there is provided a semiconductor device comprising a semiconductor chip and a flexible substrate that includes a base substrate and an interconnecting pattern formed on the base substrate,
wherein the base substrate has a light transmission property; and
wherein the interconnecting pattern on the base substrate is electrically connected to electrodes formed on the semiconductor chip.
(10) The semiconductor chip may be connected to the interconnecting pattern by the face down bonding.
(11) According to a fourth aspect of the present invention, there is provided an apparatus for manufacturing a semiconductor device, comprising:
a first transportation means for transporting a flexible substrate;
a second transportation means for transporting a semiconductor chip; and
a detection means for position detecting,
wherein the detection means is located on a side opposite to a side on which the semiconductor chip is provided to detect a position of an interconnecting pattern formed on the flexible substrate or a position of electrodes formed on the semiconductor chip.
(12) According to a fifth aspect of the present invention, there is provided a circuit board on which the above-described semiconductor device is mounted.
(13) According to a sixth aspect of the present invention, there is provided an electronic instrument comprising the above-described circuit board.